What the FDA labels say about taking them together
Lithium and verapamil
Verapamil's FDA label of April 6, 2026 names lithium in its drug interactions section; the lithium labels PlainMeds reads (4) do not name verapamil. The verapamil label: “Increased sensitivity to the effects of lithium (neurotoxicity) has been reported during concomitant verapamil-lithium therapy with either no change or an increase in serum lithium levels.”
Check it at the source: the lithium FDA label on DailyMed (effective December 23, 2025, Glenmark Pharmaceuticals Inc., USA); the verapamil FDA label on DailyMed (effective April 6, 2026, Zydus Pharmaceuticals (USA) Inc.).
What does the lithium label say about verapamil?
Lithium's label (effective December 23, 2025) and its 3 other brand-application labels do not name verapamil in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Lithium Carbonate), Glenmark Pharmaceuticals Inc., USA, effective December 23, 2025 (SPL set 63b3790f-a9b5-47f4-bae1-ddf8b43c13c1), via openFDA; the full label on DailyMed
What does the verapamil label say about lithium?
Verapamil label, drug interactionsIncreased sensitivity to the effects of lithium (neurotoxicity) has been reported during concomitant verapamil-lithium therapy; lithium levels have been observed sometimes to increase, sometimes to decrease, and sometimes to be unchanged.
Verapamil Hydrochloride label (Wilshire Pharmaceuticals, Inc., November 27, 2024), drug interactionsIncreased sensitivity to the effects of lithium (neurotoxicity) has been reported during concomitant verapamil-lithium therapy with either no change or an increase in serum lithium levels.
Source: FDA drug label (Verapamil Hydrochloride, NDA020943), Wilshire Pharmaceuticals, Inc., effective November 27, 2024 (SPL set 5f665d08-e1e4-422a-88c2-d8834abf9e1a), via openFDA
Source: FDA drug label (Verapamil hydrochloride), Zydus Pharmaceuticals (USA) Inc., effective April 6, 2026 (SPL set e19ab8d8-dae5-489d-9805-7e7407bea06d), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Lithium | Verapamil | |
|---|---|---|
| Labeled for | Bipolar disorder | High blood pressure, Atrial fibrillation, Angina |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.104 per capsule 300 mg capsule | $0.191 per tablet 180 mg tablet |
| Shortage now | No current entry | A presentation being discontinued |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once